Discussions By Condition: I cannot get a diagnosis.

Abdominal pain in 10-yr-old boy

Any thoughts as to what may cause abdominal pain in 10-year-old boy? Pain is in central, lower part of abdomen and slightly to the right for 15 days. He is able to consistently pinpoint the spot which causes the most pain and tenderness is observed on exam. Also complains of nausea and a feeling of being cold. Normal bowel movements with the exception of 4 episodes of diarreha in 5 days. No fever or other symptoms. U/S ruled out appendicitis. Bloodwork and urinalysis are all normal with the exception of a slightly elevated SED rate (rate was 19, we were told 15 was target but 19 was not immediate cause for concern). We have been to pediatrician 3 times, ER twice and GI once. 3rd round of labs ordered today. Any thoughts as to what it could be or what we should be asking for? Thanks for the help!